Glucose administration augments in vivo uptake and phototoxicity of the tumor-localizing fraction of hematoporphyrin derivative.

Rhabdomyosarcoma tumors in rats made hyperglycemic by multiple injections of glucose exhibited a transient decrease in pH and an increased ability to accumulate derivatives of hematoporphyrin (HPD). Photoradiation of tumors in glucose/HPD-treated animals produced a greater cell kill than in galactose/HPD-treated controls. A therapeutic benefit of glucose administration in conjunction with HPD-phototherapy is suggested.